Big Babies (Large for Gestational Age), Small Babies (Small for Gestational Age), and Blood Sugar
Some babies are born at over eight and a half pounds. Maybe they are just big babies, but maybe there is a medical reason the baby is so big. The most common reasons are that mom had undetected blood sugar problems, or she knew she had diabetes and it was hard to control.
So when a baby is born over eight and a half pounds, the nurses check her blood sugar frequently for the first 12 hours or until the blood sugar is recorded at a safe level three times in a row.
Some babies are born under five and a half pounds. Maybe they are just small babies, but maybe there is a medical reason the baby is so small. The most common reasons are that the placenta wasn't working right, or there is a medical problem with the baby.
A small baby doesn't have reserve fat on his body, so he can have trouble keeping his blood sugar at a safe level. The nurses check his blood sugar frequently for the first 12 hours to make sure it is stable, just like in big babies.
A safe blood sugar for a newborn is over 40. That would be a low blood sugar for a child or an adult, but in a baby, over 40 is OK. If the baby's blood sugar is less than 40, the baby must be fed right away. A low blood sugar is dangerous to our brains if it lasts too long.
Thanks to Janelle Aby MD, Stanford School Of Medicine, Newborn Nursery, and Lucille Packard Children's Hospital for the use of occasional photographs.